G3XBM's Fredbox 10mW 2m AM Transceiver

A look at the Fredbox transceiver. First built in 1974 and recently rebuilt, this little homebrew transceiver puts out 10mW AM on 2m. It uses a super-regenerative receiver and a simple series modulated AM transmitter. Lots of local contacts, several at 100kms and one international one at 160kms across the English Channel. All these were made handheld with a whip antenna and the internal battery. The rig is described on my website http://www.g3xbm.co.uk . Articles on the Fredbox and its derivative the Sixbox have now appeared in many magazines in the UK, Germany and in Japan.

Category:

Science & Technology

Tags:

• fredbox
• transceiver
• am
• qrp
• radio
• ham
• g3xbm 2m
• 144mhz
• vhf
• amplitude
• modulation
• handheld
• amateur
• ham radio
• 2m
• walkie-talkie
• amateur radio
• super-regenerative
• superregen
• regen

[3mustardMoNkEyS]

Is that a BNC connector for the antenna? And also would it be better if I used an RC filter for the transmitting PA or an LC filter?

[G0IFI]

What a great little project. People just don't know how much fun the hobby can be when you try these things. Sadly, it's easier to get the credit card out than the soldering iron. My first 2 metre RX was a superregen, and recently I cobbled up a regen for 40, 80 and 160 which works just perfectly for general listening, and cost er, nothing. All with bits torn out of old PCBs.

This is real radio. Thanks for posting it.

[PA3DMI]

Very nice, fun project ! 73 from Amsterdam

[LinkFamilyPA]

thats cool!! thanks for the video

[Valdek65]

Impress!!!!!!amazing!!! SQ 8 GEW